Abstract:

A rotation-activated electronic component, preferably a RFID tag mounted
on or incorporated in a support that is rotated when read, e.g. a CD or
DVD. The RFID tag comprises an antenna, a rotational switch and a
component, advantageously a processor. The antenna is adapted to
transform received RFID signals to electric energy that powers the
component. In a preferred embodiment, the rotational switch is adapted to
cut the circuit unless the support does not rotate at or above a certain
rotational speed. Supports equipped with the RFID tag of the invention
will thus respond only if they rotate sufficiently. This can avoid
collisions in case more than one such RFID tag is within communication
range of an antenna of a reader. In a preferred embodiment, the
information returned by the component is needed for full use of the
content on the support.

Claims:

1. An electronic device comprising:communication means adapted to interact
with an external device;a power source;a component adapted to process
first information received from the communication means and to send
second information to the communication means, the second information
being intended for the external device; anda switch adapted to enable
communication via the communication means whenever it is subjected to
predetermined rotational speed and disable communication via the
communication means whenever it is not subjected to predetermined
rotational speed.

2. The electronic device of claim 1, wherein the switch enables
communication when the rotational speed is above a threshold value.

3. The electronic device of claim 1, wherein the component comprises a
processor.

4. The electronic device of claim 1, wherein the communication means is an
antenna.

5. The electronic device of claim 4, wherein the electronic component is a
Radio Frequency Identification tag.

6. The electronic device of claim 4, wherein the antenna is further
adapted to function as the power source by transforming Radio Frequency
signals to electric energy.

7. The electronic device of claim 1, wherein the power source is a
battery.

8. An information medium adapted to store content and comprising an
electronic device according to claim 1.

9. The information medium of claim 8, wherein access to content stored on
the information medium is enhanced or enabled by information accessible
from the electronic device.

10. The information medium of claim 8, wherein the information medium is
an optical disc.

Description:

TECHNICAL FIELD

[0001]The present invention relates generally to electronic components,
and more particularly to an electronic component that is activated or
deactivated by rotation.

BACKGROUND

[0002]This section is intended to introduce the reader to various aspects
of art, which may be related to various aspects of the present invention
that are described and/or claimed below. This discussion is believed to
be helpful in providing the reader with background information to
facilitate a better understanding of the various aspects of the present
invention. Accordingly, it should be understood that these statements are
to be read in this light, and not as admissions of prior art.

[0003]Radio-frequency identification (RFID) uses an object, an RFID tag
(hereinafter "tag"), which interacts with transmitted radio waves, for
example in systems for theft prevention, supply chain management or
access to buildings. A typical tag comprises at least two parts: an
antenna that receives and transmits a radio-frequency (RF) signal, and an
integrated circuit that stores and processes information and processes
the signal. Some tags, called "active", comprise a battery and are thus
autonomous, while "passive" tags have no battery and therefore have to
rely on external power, often the received RF signal, in order to
function properly.

[0004]U.S. 2008/0307884 describes a non-contact shock sensor, which may be
used to detect if an object has been submitted to shocks during
transport. The sensor comprises a RFID chip, a conductor loop and a
movable mass. When submitted to sufficient acceleration, the mass breaks
the loop, which can thereafter be read out via the RFID chip.

[0005]U.S. 2009/0299570 describes a tire module for making tire
measurements that, presumably, are sent to a processor in the vehicle on
which the tire is mounted. In order to reduce the load on a battery, it
is proposed to activate the module only when the tire has reached a
predetermined velocity.

[0006]It has also been proposed, for example in WO 2006032613 and U.S.
Pat. No. 6,357,005, to use tags on or in digital supports such as CDs and
DVDs. This may for example be done in order to protect the content on the
digital support (information necessary to access the content is comprised
in the tag) or to store preferences regarding the playback of the
content.

[0007]While this works well in most cases, there may be problems if there
are more than one tag within range of the reader. This may for example be
the case when a user puts DVDs on the DVD player, since the tags on these
DVDs may be as close as the one in the player. One problem with this, in
particular for passive tags, is that the signal power emitted by the
reader has to be shared, which may lead to decreased communication
quality. A further problem is that it may be difficult for the reader to
know exactly which response to take account of. For example, if one DVD
returns that it should be played at volume 7 and another DVD requires
volume 16, the reader would not know which volume value to choose.

[0008]It can therefore be appreciated that there is a need for a solution
that overcomes these problems and allows a reader to interact with the
present tag without disturbance from other tags.

[0009]An obvious solution to this problem would be to shield the readers,
but the present invention provides a different, surprising solution to
the problem, as will be seen in the description of the preferred
embodiments hereinafter.

SUMMARY OF INVENTION

[0010]In a first aspect, the invention is directed to an electronic device
comprising communication means adapted to interact with an external
device, a power source and a component adapted to process first
information received from the communication means and to send second
information intended for the external device to the communication means.
The electronic device further comprises a switch adapted to enable
communication via the communication means when it is subject to
predetermined rotational speed and to disable communication via the
communication means when it is not subject to predetermined rotational
speed.

[0011]In a first preferred embodiment, the switch enables communication
when the rotational speed is above a threshold value.

[0012]In a second preferred embodiment, the component comprises a
processor.

[0013]In a third preferred embodiment, the communication means is an
antenna. The electronic component is advantageously a Radio Frequency
Identification (RFID) tag. It is also advantageous that the antenna is
further adapted to function as the power source by transforming Radio
Frequency (RF) signals to electric energy.

[0014]In a fourth preferred embodiment, the power source is a battery.

[0015]In a second aspect, the invention is directed to an information
medium adapted to store content and comprising an electronic device
according to any of the embodiments of the first aspect.

[0016]In a first preferred embodiment, access to content stored on the
information medium is enhanced or enabled by information accessible from
the electronic device.

[0017]In a second preferred embodiment, the information medium is an
optical disc.

BRIEF DESCRIPTION OF DRAWINGS

[0018]Preferred features of the present invention will now be described,
by way of non-limiting example, with reference to the accompanying
drawings, in which

[0020]FIG. 2 schematically illustrates a tag according to a preferred
embodiment of the present invention;

[0021]FIGS. 3a and 3b illustrate a first preferred embodiment of a
rotational switch;

[0022]FIGS. 4a and 4b illustrate a second preferred embodiment of a
rotational switch;

[0023]FIGS. 5a and 5b illustrate a third preferred embodiment of a
rotational switch using conductive liquid;

[0024]FIG. 6 illustrates a fourth preferred embodiment of a rotational
switch according to the invention; and

[0025]FIGS. 7a and 7b illustrate a medium equipped with a tag according to
a preferred embodiment of the present invention

DESCRIPTION OF EMBODIMENTS

[0026]A main inventive idea of the present invention is the use of a
module that is controlled by rotation. An exemplary, non-limitative use
that will be used hereinafter is the activation of a tag positioned on an
optical medium such as a DVD.

[0027]FIG. 1 illustrates the basic idea of the present invention. A tag
110 is fixed to a rotating support 100, i.e. a support that may rotate.
The tag 110 comprises a power source 112, a rotational switch 114 and a
component 116 that preferably has processor and memory capabilities, i.e.
it comprises a processor and memory. The nature of the power source 112
depends on whether the tag 110 is active or passive. If the tag is
active, then it may for example be a battery; if the tag is passive, then
it is preferably an antenna that transforms received RF signals to
energy. The component 116 uses the energy from the power source 112 to
function, e.g. to process RF signals, as discussed hereinbefore. Located
between the power source 112 and the component 116 is a rotational switch
114. In a preferred embodiment, the rotational switch 114 is arranged to
cut the electric contact between the power source 112 and the component
116 unless it is subject to sufficient rotational speed, as will be
further described hereinafter. In a variant embodiment, the rotational
switch 114 is on the contrary arranged to cut the electric contact when
subject to sufficient rotational speed. It will thus be appreciated that,
in the preferred embodiment, the component 116 is not powered if the
rotating support does not rotate quickly enough; in the variant
embodiment, the opposite applies. Naturally, when the component 116 is
powered, it functions as a powered component of a prior art tag would do,
notably communicating with a RFID reader.

[0028]The skilled person will appreciate that when the DVD is not rotating
(or does not rotate at a sufficient speed), the rotational switch 114
cuts the power supply, which for example can mean that only the DVD in
the player will respond (provided that it rotates), while DVDs lying on
the player will not, no matter how close to the RFID reader they come.
Thus, collisions can be avoided and the signal power can be `reserved`
for a single tag.

[0029]FIG. 2 schematically illustrates a tag according to a preferred
embodiment of the present invention. The tag 210, which is fixed to or
part of a rotating support 100, comprises a component 116, a power source
embodied by an antenna 212, and a rotational switch 214. The antenna 212
is adapted for RF communication, i.e. transmission and reception of RF
signals, and as a power supply by transforming RF signal energy to
electrical energy. The rotational switch 214 comprises a first part that
is movable so as to break the shortcut connection when subject to
sufficient rotational energy and to establish the connection when it is
not. The skilled person will appreciate that the use of a shortcut
connection is preferably only used when the power source is an antenna,
but not when it is a battery.

[0030]The skilled person will appreciate that it is also possible to
arrange the antenna 212, the rotational switch 214 and the component 116
in series (something that holds true for any suitable embodiment).

[0031]FIGS. 3a and 3b illustrate a first preferred embodiment of a
rotational switch. The first preferred embodiment, "Idle On", does not
power a tag in the absence of rotational energy.

[0032]The rotational switch 114 comprises a housing 310. A first and a
second electrode 330, 340 enter the housing 310 but are arranged at a
distance from one another. The space between the first and the second
electrode 330, 340 can be bridged by a movable conducting connector 350,
which is arranged on a spring 360. A weight 320 is arranged on the
connector 350, but this weight 320 may naturally be an integral part of
the connector 350.

[0033]FIG. 3a shows the situation where no or insufficient rotational
speed is imparted on the rotational switch 114. In this case, the
connector 350 connects the first and second electrodes 330, 340 thereby
causing a short circuit, which in turn means that a component arranged in
parallel is not powered. In other words, when the rotational switch 114
does not rotate sufficiently, the component is idle.

[0034]FIG. 3b shows the situation where sufficient rotational speed 370 is
applied to the rotational switch 114. The force imparted by the rotation
on the weight 320 and the connector 350 is now greater than the opposite
force provided by the spring 360. This breaks the contact between the
first and second electrodes 330, 340, which means that the short circuit
is no longer working. The energy provided by a power source then reaches
the component, thereby powering the same.

[0035]FIGS. 4a and 4b illustrate a second preferred embodiment of a
rotational switch. The second preferred embodiment, "Idle Off", powers a
tag in the absence of rotational energy.

[0036]The rotational switch 414 of the second preferred embodiment
resembles that of the first preferred embodiment quite a bit. The housing
310, the first and second electrodes 330, 340, and the weight 320 can be
practically the same. However, the connector 450 and the spring 460 are
now arranged so that no connection is made in the absence of rotational
force. When such force 370 is applied, however, do the weight 320 and the
connector 450 press against the opposite force provided by the spring
460, so as to bridge the gap between the first and second connector 330,
340 when the rotational speed 370 is sufficient. This completes the short
circuit, thereby depriving a component of the power provided by a power
source.

[0037]The skilled person will appreciate that the expressions "Idle On"
and "Idle Off" apply when the rotational switch 314, 414 is arranged in
parallel with component and that the opposite holds true when the
rotational switch 314, 414 is arranged in series therewith.

[0038]FIGS. 5a and 5b illustrate a third preferred embodiment of a
rotational switch using conductive liquid. The third preferred embodiment
can be "Idle Off" if arranged in parallel with a component and "Idle On",
if arranged in series.

[0039]The rotational switch 514 comprises a housing 510 adapted to receive
a first and a second electrode 530, 540, each of which is isolated expect
at, preferably, the end part 532, 542 located inside the housing 510. The
housing 510 also comprises a conductive liquid 550, for example mercury,
arranged so that it is in contact with the end parts 532, 542 regardless
of the position of the rotational switch 514, as long at it is still or
not subject to sufficient rotation. FIG. 5a is for illustrative purposes
only; for example, the meniscus caused by the liquids adhesion to the
walls of the housing 510 is not shown.

[0040]FIG. 5b illustrates the rotational switch 514 when subjected to
sufficient rotational energy 370. As can be seen, the conductive liquid
550 is now `deformed`, thus creating a liquid-free space around the end
parts 532, 534, thus breaking the connection between them.

[0041]FIG. 6 illustrates a fourth preferred embodiment of a rotational
switch according to the invention. The fourth embodiment is relatively
close to the third embodiment. The rotational switch 614 comprises the
same features: a housing 610, a first and second electrode 640, 642 with
non-isolated end parts 632, 642, and a conductive liquid 650. The main
difference is the arrangement of the first and second electrodes 630,
640. In the fourth embodiment, they are arranged in a `radial` way; at
sufficient rotation, the second electrode 640 is completely free of
liquid 650, while the first electrode 630 still is in contact therewith.

[0042]The speed for closing or opening the contact between the first and
second electrodes depends on at least the following factors that can be
selected to obtain a desired value: [0043]size of the housing,
[0044]fluid amount and viscosity [0045]size and position of the
electrodes [0046]distance of the rotational switch from the rotation
centre.

[0047]A further example of a rotational switch is found in U.S.
2006/0250923. The rotational switch comprises a cantilever made up of a
beam having a mass at its end. The cantilever is arranged, during
rotation, to close a circuit from a voltage source to a voltage sensitive
region. The voltage source is autonomous, i.e. it generates electricity
using only the rotation of the disk. The voltage sensitive region is
arranged to change the optical characteristics of the surface of a DVD to
ensure that the data stored in the underlying area cannot be read. It
will be immediately appreciated that the use of this switch, the DVD
equipped with such a switch and indeed the entire technical problem is
quite distant from the present invention.

[0048]FIGS. 7a and 7b illustrate a medium 700, e.g. a DVD, equipped with a
tag 710 according to a preferred embodiment of the present invention. The
medium 700 is within communication range of an antenna 720 of an external
device, such as a reader for the medium 700, e.g. a DVD player.

[0049]In FIG. 7a, it is illustrated how the antenna 720 that sends RF
energy 722 towards the antenna (not shown) of the tag 710. However, as
the medium does not rotate sufficiently to power the component (not
shown) of the tag 710, the tag 710 does not respond.

[0050]FIG. 7b, on the other hand, illustrates the case when the medium 700
and its tag 710 are subject to sufficient rotational energy 730 for the
rotational switch (not shown) to engage so as to power the component. In
this case, when the antenna 720 sends a RF signal 724 to the tag 710, the
latter is able to process the information in the signal 724 and send a
response 726.

[0051]In a preferred embodiment, the information provided by the tag 710
enables use--possibly enhanced or improved--of the content on the medium
700. To obtain this information, the reader sends a RF signal to the tag
that returns the required information. For example, the information may
be a decryption key, the result of a computation performed by the tag's
component (i.e. its processor), information related to the rendering of
the content on the medium (such as volume, language, subtitles), or, in
the case of a computer game, information about the current state of the
game (such as character equipment and characteristics, available cars and
race tracks . . . ).

[0052]It will be appreciated that other types of movement than rotational
may be envisaged; any kind of suitable acceleration may act on the switch
to enable or disable communication. For example, sufficient linear
acceleration in the right direction may act upon the switch illustrated
in FIGS. 3A, 3B, 4A and 4B.

[0053]It will be appreciated that the present invention can avoid
ambiguity for the reader, as it will receive a single response to a RF
signal that it sends while having multiple receivers within communication
distance. In the case of using prior art support, it would receive
multiple responses from supports within communication distance of the
reader.

[0054]It will be appreciated that a tag is a convenient and economic way
of manufacturing the module, as it may then be affixed to any suitable
support. It is however also possible to include the tag as a part of a
bigger structure, e.g. by including it in the support.

[0055]It will further be appreciated that the present invention can
prevent communication collisions in environments with multiple tags,
while the solution is completely transparent to the user.

[0056]Each feature disclosed in the description and (where appropriate)
the claims and drawings may be provided independently or in any
appropriate combination. Reference numerals appearing in the claims are
by way of illustration only and shall have no limiting effect on the
scope of the claims.